The process of electrophoresis has gained notoriety in recent years as a method of performing difficult separations, particularly separations involving organic materials in solutions. Thus, in biochemical applications, for example, organic compounds such as peptides, proteins, nucleic acids, antibodies and the like may be separated in solutions containing them by the utilization of electrophoretic techniques. These techniques have generally involved the utilization of columns having tubes and packing and applying electrical charges to the tubes to electrically move the components of the solution and separating them based on their electrophoretic mobility. A typical patent describing such a separation is U.S. Pat. No. 3,533,935.
In a similar vein attempts have been made to utilize capillary tubes for the purpose of conducting the electrophoretic separation. In these processes the separation is conducted inside of the tube. Typical examples of such operations are those described in U.S. Pat. No. 3,620,958 and U.S. Pat. No. 3,941,678.
One of the more serious problems encountered in conducting electrophoretic separations on a larger scale is the generation of heat caused by the electrical current passing across the tube or vessel filled with the electrolyte in which the electrophoresis is taking place. This requires special cooling techniques and a patent describing the problem associated with cooling and one system for conducting cooling is described in U.S. Pat. No. 4,177,130.
In order to overcome convection, various anti-convective media are used such as gels and porous membranes.
Gel electrophoresis has been utilized in the art by employing gels in an array of individual tubes. In general, these processes are of a batch nature and a typical process is shown in U.S. Pat. No. 4,747,919.
Porous membranes were used in PCT International application 7900,942 for the purpose of preventing convection and streamlining the flow of the liquid in an electrophoretic separation.
However, anti-convective media make cooling inefficient and difficult. For this reason the liquid undergoing separation is cooled typically outside the electrophoretic chamber, as shown in this PCT application.
While the prior art has successfully demonstrated that electrophoresis can be conducted and that solutions containing multiple components can be separated utilizing these methods, difficulty has been encountered in translating that technology to a continuous phase operation so that the separations can be conducted continuously with the recovery of the components of a given solution being made on a continuous basis. Further, in scaling up prior art processes the art faces a major problem in that considerable heat which is generated has to be dealt with effectively. If it is not, the separations attempted will not be effective due to the generation of convective currents in the electrophoretic chamber. Further, in the case of solutions containing thermally sensitive biochemical components, these components can be destroyed.
Thus, a need exists to provide electrophoretic systems that, while capable of conducting viable separations, provide easy heat removal even when the process is scaled up to separations of large quantities of material. The need to remove heat effectively from both batch and continuous electrophoretic separations also is present. It should be done in an effective and uncomplicated manner.